5 The people of Nineveh believed God's message, and from the greatest to the least, they declared a fast and put on burlap to show their sorrow. 6 When the king of Nineveh heard what Jonah was saying, he stepped down from his throne and took off his royal robes. He dressed himself in burlap and sat on a heap of ashes. 7 Then the king and his nobles sent this decree throughout the city: "No one, not even the animals from your herds and flocks, may eat or drink anything at all. 8 People and animals alike must wear garments of mourning, and everyone must pray earnestly to God. They must turn from their evil ways and stop all their violence.
Matthew Henry's Commentary on Jonah 3:5-8
Commentary on Jonah 3:5-10
(Read Jonah 3:5-10)
There was a wonder of Divine grace in the repentance and reformation of Nineveh. It condemns the men of the gospel generation, Psalm 66:18. The work of a fast-day is not done with the day. The Ninevites hoped that God would turn from his fierce anger; and that thus their ruin would be prevented. They could not be so confident of finding mercy upon their repentance, as we may be, who have the death and merits of Christ, to which we may trust for pardon upon repentance. They dared not presume, but they did not despair. Hope of mercy is the great encouragement to repentance and reformation. Let us boldly cast ourselves down at the footstool of free grace, and God will look upon us with compassion. God sees who turn from their evil ways, and who do not. Thus he spared Nineveh. We read of no sacrifices offered to God to make atonement for sin; but a broken and a contrite heart, such as the Ninevites then had, he will not despise.